I felt it was important to say why people would pray to all the gods, including the “evil” ones. I think in the case of evil gods it simply a question of placate vs. supplicate. And sometimes even the evil gods have something that you might need one day.

Gods

Benefits

Drawbacks

Orcus, demon lord of the undead, patron of all short lived intelligent species such as goblins, vanquishes death

Priests may raise the dead

Demands cruel sacrifice

Tsathoggua, frog lord, lord of swamps, ponds, rain, and slime; lord of slaadi, protector of stirges, the god of sloth and of gluttony

Secures plant fertility, fends of winter

Fear of pestilence brought by morbid swamps and blood-sucking insects

Hecate, goddess of witches, queen of the night, forbidden lore, mollified by pig slaughter on nights of the full moon